A conventional probe apparatus includes: a loader chamber for transferring a target object to be inspected such as a semiconductor wafer or the like; a prober chamber for inspecting electrical characteristics of the target object transferred from the loader chamber; and a control unit for controlling the loader chamber and the prober chamber. The conventional probe apparatus serves to transfer the target object from the loader chamber to the prober chamber, inspect the electrical characteristics of the target object in the prober chamber, and return the inspected target object to the original location, under the control of the control unit.
The prober chamber has: a mounting table accommodating therein an elevation mechanism, for mounting thereon the target object; an XY table for moving the mounting table in X and Y directions; a probe card disposed above the mounting table moving by the XY table; and an alignment mechanism for aligning a plurality of probes of the probe card with a plurality of electrode pads of the target object mounted on the mounting table. The inspection is performed while keeping the target object mounted on the mounting table at a predetermined temperature by a temperature control unit installed in the mounting table. Moreover, a test head is rotatably provided on a top surface of the prober chamber, and is electrically connected to the probe card through a performance board (not shown).
The probe apparatus performs high-temperature inspection by heating the target object to a high temperature of, e.g., about 100° C. or higher, or low-temperature inspection by cooling the target object to, e.g., several tens of minus degrees. When the high- or the low-temperature inspection is carried out, the target object is heated or cooled to a predetermined inspection temperature by using the temperature control unit installed in the mounting table. The temperature control unit has a heating unit and a cooling unit.
For example, when the target object is subjected to the high-temperature inspection, the target object mounted on the mounting table is heated to, e.g., about 100° C., by using the temperature control unit installed in the mounting table. Next, the probes of the probe card are aligned with the target object by the alignment mechanism, and are then brought into contact with the target object. Thereafter, the target object is overdriven to inspect electrical characteristics of the target object at a temperature of about 100° C.
In an initial stage of the inspection, the target object is heated to a high temperature of about 100° C., whereas the probe card is not heated. Therefore, a large temperature difference exists between the target object and the probes. Accordingly, when the probes are brought into contact with a first chip of the target object, the probes are heated by the target object and thus are extended by thermal expansion. Further, a main body of probe card is gradually heated by the heat transferred from the target object to be thermally expanded.
As the inspection on the chips in the target object is repeated, the temperatures of the probe card main body and the probes are gradually raised, so that the tip positions of the probes are gradually displaced from the respective original positions. In that state, if the target object is overdriven by a normal overdrive amount, a probe pressure from the probes excessively increases to thereby inflict damages on the probes or the target object. Further, owing to the displacement of the tip positions, the positions of the probes and the target object are gradually misaligned, so that they are not in tight contact with each other. As a result, the reliability of the inspection may deteriorate.
Therefore, Japanese Patent Laid-open Publication No. 2007-088203 (JP2007-088203A) discloses a method for inspecting a target object to be inspected by preheating a probe card to a temperature close to a temperature of the target object before the inspection. In JP2007-088203A, since the probe card is preheated in a state where the target object heated to a predetermined temperature directly contacts with probes of the probe card, the preheating time can be shortened.
In JP2007-088203A, although the preheating time can be reduced by preheating the probe card in a state where the target object heated to a predetermined temperature is brought into direct contact with the probes of the probe card, the preheating time is still required. Moreover, in this technique, the overdrive amount can be precisely set by correcting only a height of the tip positions of the probes based on a temperature, i.e., a thermal expansion.
However, the probes are extended in a horizontal direction as well as in a height direction, and it is difficult to solve the misalignment in the horizontal direction between the probes and the target object. Besides, depending on types of probe cards, the probes do not properly contact with the electrode pads of the target object, whereby the reliability of the inspection may deteriorate. These drawbacks occur in a low-temperature inspection as well as in a high-temperature inspection.